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321.
Alison M. Strange Geoffrey H. Griffiths Sophie Hine Kim Young Graham J. Holloway 《Journal of Insect Conservation》2007,11(3):241-249
The Small Red Damselfly (Ceriagrion tenellum) (De Villiers) (Odonata: Coenagrionidae: Ceriagrion) is classed as vulnerable (Shirt, British Red Data Book, Nature Conservancy Council, Peterborough, UK, 1987) throughout the
UK, and is included in certain Local Biodiversity Action Plans (LBAPs) in the south. A large proportion of any Biodiversity
Action Plan is concerned with the requirement of conservation and management programmes. In order to guide them, information
about the habitat preferences of the species concerned is vital. Detailed habitat information was collected to include a variety
of physical parameters particularly vegetation, both in-channel and bankside. The species was found to be primarily associated
with in-channel emergent broad-leaved plants, bankside grasses and rushes, and shallow, narrow channels with dark organic
substrate. The consequences of these findings are discussed in relation to the conservation and management of C. tenellum.
相似文献
Alison M. StrangeEmail: |
322.
G J Beckett A F Howie R Hume B Matharoo C Hiley P Jones R C Strange 《Biochimica et biophysica acta》1990,1036(3):176-182
The developmental expression of the alpha-, mu- and pi-class glutathione S-transferases has been defined in human lung and kidney using radioimmunoassay, immunohistochemistry and column chromatography. Expression of alpha-class enzymes increased significantly after about 40 weeks gestation in kidney but not lung, while expression of mu isoenzymes was continuous throughout development in both tissues. Expression of the pi isoenzyme fell during in utero ontogeny in lung, the pattern of down-regulation being similar to that previously observed in liver. There was no change in the expression of this isoenzyme in kidney. Comparison of the expression of the glutathione S-transferases in developing lung, kidney and liver shows some common patterns of expression suggesting these genes are under similar regulatory control. 相似文献
323.
324.
325.
Zerroug MM Laouer H Strange RN Nicklin J 《Communications in agricultural and applied biological sciences》2010,75(4):721-724
Biological control such as the use of plant extracts has emerged as promising option to the phenomena of fungi resistance to chemical. Several constituent of essential oil have been studied for their biological activity including antibacterial and antifungal activity. In this study the effect of Ammoides pusilla essential oil with different concentrations was test against the growth of Ascochyta rabiei and the production of solanapyrone A by the fungus. After 14 days the mycelium was collected and the dry weight measured. A. rabiei did not grow at a final concentration of 6 and 3 mg/ml, at 1.5 mg/ml and 0.625ml there was little growth of the fungus with a dry weight of 55 mg and 99 mg respectively compared to the control with 519 mg dry weight, but there was no solanapyrone A produced. However a new compound appeared at the HPLC at 10 min. 30 sec. compared with the solanapyrone A which elutes at nearly 14 minutes. 相似文献
326.
Circumstantial evidence for phytoalexin involvement in the resistance of peanuts to Aspergillus flavus 总被引:1,自引:0,他引:1
Three stilbene phytoalexins, elicited by slicing and incubating imbibed peanut kernels under aerobic conditions, inhibited spore germination and hyphal extension of Aspergillus flavus with ED50 values in the range 4.9-12.8 micrograms ml-1. Phytoalexin yield was dependent on cultivar, conditions and duration of incubation after slicing, and crop history. The yield of phytoalexin from ten cultivars studied, after slicing and incubating at 25 degrees C for 24 h, ranged from 28 to 935 micrograms per g fresh weight and was negatively correlated with dry kernel colonization by A. flavus [r = -0.868 when plotted as 1n (phytoalexin concn) against 1n (percentage peanut colonization)]. When the incubation period was extended to 96 h there was no such correlation. Reduced phytoalexin yields were obtained when sliced kernels of one cultivar studied were incubated in water or at 37 degrees C, and no phytoalexin was obtained when the slices were incubated under nitrogen gas or frozen before aerobic incubation. Drought stress during pod development in four cultivars studied reduced phytoalexin yields of sliced kernels incubated at 25 degrees C for 24 h by 17-65% compared with non-stressed controls. 相似文献
327.
The glycosylation properties of D2 dopamine receptors from striatal and limbic areas of bovine brain. 总被引:1,自引:0,他引:1 下载免费PDF全文
D2 dopamine receptors from bovine brain (caudate nucleus and olfactory tubercle) have been solubilized using sodium cholate/NaCl and their glycoprotein properties studied in terms of their interaction with wheat-germ agglutinin-agarose (WGA-agarose). Under optimal conditions about 65% of the applied D2 dopamine receptors bound to WGA-agarose and could be eluted with N-acetylglucosamine. The ability of receptors to adsorb to the affinity column was shown to be dependent on the cholate and salt concentrations used. Digestion of the membrane bound D2 dopamine receptors with neuraminidase prior to solubilisation reduced the ability of the receptors to bind to WGA-agarose (50% of applied receptors bound) whereas digestion with N-acetylglucosaminidase did not significantly affect binding to WGA-agarose. Digestion with the two enzymes together resulted in a larger decrease in binding to WGA-agarose than was seen with the two enzymes alone (40% of applied receptors bound). Stepwise elution of bound receptors from the WGA-agarose columns using 2.5 mM- and 100-mM-N-acetylglucosamine showed that about 40% of the bound receptors interacted with WGA-agarose in a low-affinity manner, the remainder showing a high-affinity interaction. Neuraminidase treatment reduced the low-affinity population suggesting that the interaction of oligosaccharides bearing sialic acid with WGA-agarose is of lower affinity and that higher-affinity binding is via N-acetylglucosamine. These data are discussed in terms of the heterogeneity of carbohydrate moieties on the D2 dopamine receptors within a brain region. In all the tests applied here, however, receptors from caudate nucleus and olfactory tubercle behaved identically so their glycosylation patterns must be very similar. 相似文献
328.
In the course of a plant disease survey of the Malaysian Peninsula (Malaysia comprises the Malaysian Peninsula, Sabah and Sarawak) during the period 1981-1986, more than 1000 isolates of Fusarium were obtained from diseased plants and seeds. Two further isolates were obtained from patients admitted to hospitals in the same area. The occurrences of F. proliferatum, F. nygamai and F. longipes are new records for the Malaysian Peninsula and the association of F. solani and F. oxysporum var. redolens with human diseases does not seem to have been reported previously. Ten representative species which could be classified into seven sections of the genus were selected for studies of their toxigenicity in liquid cultures and/or on rice. Crude toxin preparations from culture filtrates or extracts of the inoculated rice were tested for toxicity to brine shrimp larvae and tobacco mesophyll protoplasts. The protoplasts were more sensitive than the brine shrimp larvae to the toxin preparations, except those from the isolates of F. solani and F. oxysporum var. redolens obtained from either humans or tobacco. The toxicity of the preparations from rice cultures per g rice was always greater than the toxicity per ml of culture filtrates from cultures grown on Czapek-Dox broth, Czapek-Dox supplemented with 1% (w/v) peptone or Czapek-Dox supplemented with 5% (w/v) tobacco extract. The activity of all toxin preparations was stable to heat. It is concluded that the occurrence of toxigenic species of Fusarium in the Malaysian Peninsula is widespread and that they may pose a serious threat to the health of human, animal and plant populations. 相似文献
329.
Cell membrane water permeability of rabbit cortical collecting duct 总被引:15,自引:0,他引:15
Summary The water permeability (P
osm) of the cell membranes of isolated perfused rabbit cortical collecting ducts was measured by quantitative light microscopy. Water permeability of the basolateral membrane, corrected for surface area, was 66 m·sec–1 for principal cells and 62.3 m·sec–1 for intercalated cells. Apical membraneP
osm values corrected for surface area, were 19.2 and 25 m·sec–1 for principal and intercalated cells, respectively, in the absence of antidiuretic hormone (ADH). Principal and intercalated cells both responded to ADH by increasingP
osm of their apical membranes to 92.2 and 86.2 ·sec–1 respectively. The ratio of the total basolateral cell membrane osmotic water permeability to that of the apical cell membrane was 271 in the absence of ADH and 71 in the presence of the hormone for both cell types. This asymmetry in water permeability is most likely due to the fact that basolateral membrane surface area is at least 7 to 8 times greater than that of the apical membrane. Both cell types exhibited volume regulatory decrease when exposed to dilute serosal bathing solutions. Upon exposure to a hyperosmotic serosal bath (390 mosm), pricipal cells did not volume regulate while two physiologically distinct groups of intercalated cells were observed. One group of intercalated cells failed to volume regulate; the second group showed almost complete volume regulatory increase behavior. 相似文献
330.
W Schmid G Scherer U Danesch H Zentgraf P Matthias C M Strange W Rwekamp G Schütz 《The EMBO journal》1982,1(10):1287-1293